New option to plsql-spec command to indicate when to capture the output

[d1egoaz]

The idea with this commit, is to provide a way to show the output when Thor runs the rspec command,

In this commit @rsim added the option to Capture the log, and there is no way to disable the option :(
8c76f47

The problem with :capture => true is that hide errors that are outside rspec, I ask about this option in the Google Group:
https://groups.google.com/forum/?fromgroups=#!topic/oracle-enhanced/SmkETvkc2i8

I added a new option "--capture" to "plsql-spec" in order to indicate when do you don't want to capture the errors:

    plsql-spec run  --capture=false

If you don't provide the capture option, the default value is true (How it works today)

    plsql-spec run

In this example I have an error in the test_spec.rb file, I'm requiring a non existing gem

require "spec_helper.rb"
require "non_existing_gem"

Before my commit, this is the output
rake probar[ejemplo] executes internally the "plsql-spec" run command

It's very difficult to catch the error

After the commit, with plsql-spec run --capture=false this is the output